Chelsea head coach Antonio Conte downplayed Jose Mourinho's pursuit of "revenge" after Manchester United's two losses at Stamford Bridge last season.
Mourinho lost 4-0 in the Premier League and 1-0 in the FA Cup to mark two miserable visits to the club he led to the Premier League title on three occasions.
The Portuguese cut a frustrated figure, but United did beat Chelsea 2-0 at Old Trafford in the return league game in April.
"Don't forget that they won 2-0 in the second game at home," Conte said ahead of Sunday's meeting between the two clubs.
"Every coach, every player, every team wants to win. Not for revenge, but because you need to win."
Conte may "need to win" more than most. The Blues will seek to bounce back from Tuesday's 3-0 Champions League loss to Roma against United.
"This is my task: to try to understand why we lost, and then to find the right solution to try and improve, to avoid other situations like this," Conte said. "The most important thing is that it is an isolated case."
Chelsea, who brilliantly won at Atletico Madrid in September, also limply lost at previously winless and scoreless Crystal Palace last month. That was before the trip to the Eternal City on Conte's first return to Italy, which ended in disappointment for the Blues boss because his team surrendered prematurely.
Those recent results have heaped pressure on Conte, with Chelsea already looking unlikely to mount a serious defence of the title they won last season.
"My disappointment was that we lost confidence early," Conte said. "We could have 50 minutes to come back in this game. Instead, in the second half, we played badly. It was for this reason, my disappointment."
N'Golo Kante could return following a six-game absence with a hamstring injury, but Victor Moses remains out.